part throttle stumble???

[raw]

I have a 99,2500, 4x4, auto. w/36k miles. Problem is when going up a hill at around 30-40 mph at part throttle it starts to stumble or surg. Kinda feels like when you are running over a rough piece of bumpy asphalt. I am not sure if it is the trans trying to upshift or the converter locking and un locking. I can mash the pedal on down and it will stop. It has a new fuel filter, also.

Any of you guys with lift pump problems , does this sound familiar?... ... thanks... ...

 

[BV]

stumble

that is the way my 99 acted for a couple of days before the throttle pedal position sensor set a code and turned on the check engine light. With my manual transmission it felt like it dropped down to an idle - not sure if you auto folks would feel that much drop through the convertor.